The virtues of the all-electric battery operated vehicle (“BEV”) have been sung by many for over a century. Thus, BEVs do not pollute the air where people live and work. They do not require a liquid cooling system, nor a transmission, nor an exhaust system, nor a catalytic converter, nor yearly inspections, nor periodic oil changes, nor a starter motor, and this is only a partial list. BEVs provide much empty space under the hood of the engine compartment, particularly where electrical motors are provided in the “in-wheel” configurations. BEVs run extremely quietly, reducing street noise levels and providing for a more pleasant living environment. Electric motors instantly start in all weather conditions, and they are comparatively smaller, sturdier, easily replaceable, and less expensive as compared to internal combustion (IC) engines. BEVs should and will provide useful operating lives that can be double the operating lives of IC driven conventional vehicles (“CV”).
Despite their many benefits, the landscape is littered with enterprises that have tried and failed to bring BEVs to the mass marketplace for automobiles. Indeed, Henry Ford provided an electric car during the 1912-1920 period, using lead acid batteries, which was discontinued because the internal combustion engine provided a much greater travel range. BEVs were basically absent in the vehicle marketplace until the early 1990s when, through the effort of the State of California, the BEV1 vehicle was developed which ran on a lead acid battery and which stored 18 kWh (“kilowatt-hour”) of energy, later replaced with a 26 kWh NIMH pack. Eventually, the BEV1 program was discontinued. More recently, hybrid vehicles (“Hybrid”) came into vogue, such as the Toyota Prius®. But Hybrids are not the subject of the present invention, because they include an internal combustion engine, with all its drawbacks. The object of this invention is to make all-electric automobiles, namely BEVs available to and affordable by the mass marketplace. This objective also eliminates the GM Chevy Volt®, which includes an IC engine.
The Nissan Leaf® is a BEV with a 24 kWh lithium-ion battery and a nominal driving range of about 100 miles, actually about 80 miles. The battery weighs about 600 pounds and is said to cost in excess of $16,000. The BMW Mini-E® has a 40 kWh battery. The Tesla Roadster® provides a 53 kWh battery constructed of 7,000 Li-Ion cells and has a price tag in excess of $100,000. The cost of replacing the battery is about $40,000. The cost of the Tesla S® BEV model also approaches $100,000, but provides a lower kWh battery. The Mitsubishi i-MiEV® has a 16 kWh lithium-ion battery. Think City® provides a lithium-ion (Li-Ion) BEV with a 24.5 kWh battery. The Israel-based Better Place Company has recently closed its doors, after attempting to provide BEVs utilizing batteries that are quickly exchanged or swapped out, wiping out a years long effort and an investment of about 850 million dollars.
Presently, the few surviving companies that manufacture BEVs sell at most a few thousand such vehicles per year, compared to millions of CVs that the major world automobile manufacturers produce yearly.
Considering the many benefits of BEVs, and other advantages including that with BEVs there is no need to truck gasoline fuel to gas stations all over the country (as electrical generating plants can be located close to the energy sources, whether they be hydraulic or gas or wind or solar energy), it is imperative to pinpoint the technical challenge(s) or hurdles that have prevented, to date, the BEVs being available to the mass marketplace. Indeed, that technical hurdle is well known and attributable to a single component, namely to the BEV's battery. Sixteen gallons of gasoline, able to propel a CV vehicle at 25 miles per gallon, will allow it to be driven a distance of approximately 400 miles. To achieve the same distance with a BEV would require more than 100 kWh of battery energy at a weight of about 2400 lbs., or more than the vehicle itself. The battery size would be on the order of five times the size of the CV's gasoline tank. The cost of the battery would be more than $50,000. Another serious drawback of batteries is that they lose a very substantial portion (about 50%) of their charge holding capacity as they age, which reduces the driving range by the same percentage.
Tesla's quick changing battery stations will not provide the answers to the needs of the mass market either. Each quick battery swapping station costs between $1,000,000 to $3,000,000 in initial infrastructure, to be able to handle and load heavy batteries that weigh well over 600 pounds. Purchasers of the Nissan Leaf® vehicles have to contend with recharging their BEV batteries every 80 miles or so, which requires going out of one's way to find a charging station and losing close to an hour, which is unacceptable. The government's cash incentive credits, currently about $7,500 per vehicle, to spur BEV purchases, are doomed to failure, because they do not address the real drawbacks that prevent adoption of electrical vehicles on a wide scale.
Roughly calculated, the cost of the battery is approximately at least twice the cost of the electricity needed to charge the battery over the life of the battery. In effect, the buyer is forced to purchase and pay in advance two-thirds of the lifetime “fuel” cost for the BEV. Also, the buyer is essentially “stuck” with the same physical battery for its entire life, which is problematic because technology improves all the time, and newer batteries come online that have greater energy densities, lower costs, etc. Yet, the original purchaser would have to lose the entire value of the battery included in the vehicle purchase price if they chose to discard the original battery prematurely. And the end user is limited to the driving range of a single battery, with no ability, similar to the IC vehicle driver, to buy and purchase gasoline fuel literally anywhere at the hundreds of thousands of gasoline stations located everywhere. Another disadvantage is that single-vehicle families cannot purchase the BEV, even if a vehicle having a 100 mile range is sufficient for their typical needs. They have to be able to accommodate the occasional need to drive hundreds of miles.
Since lead-acid batteries have a low energy density, i.e., stored charge per unit weight or volume, the industry has moved to lithium-ion battery types. Lithium cobalt oxide (LiCoO2) batteries offer high energy density and are used only in hand-held electronic devices because they present safety risks when damaged in an automobile crash. BEV vehicles more typically use lithium ion phosphate (LFP), lithium manganese oxide (LMO) and/or lithium nickel manganese cobalt oxide (NMC) batteries that offer somewhat lower energy density, but longer lives and inherent safety. Lithium nickel cobalt aluminum oxide (NCA) and lithium titanate (LTO) are also usable. The Chevy Volt® and the Nissan Leaf® use lithium manganese batteries. The Tesla BEVs use lithium cobalt batteries. The Better Place vehicles use lithium ion phosphate batteries. But, as noted above, the battery power that can be located in the space that is currently occupied by a gasoline tank will only produce about 80 miles of driving with a battery price tag on the order of $20,000, which is entirely unacceptable.
Battery parameters that require understanding include: Specific Energy, Energy Density, Specific Power, Charge/Discharge Efficiency, Self-Discharge Rate, Cycle Durability, and Nominal Cell Voltage. For a lithium ion battery, the Specific Energy is the energy stored per unit weight, typically 100-265 Wh/kg. For some perspective, if 25 kWh is needed to drive 80 miles (quite realistic), the weight of the battery would have to be (assuming a specific energy of a 100 Wh/kg) 150 kg (about 552 pounds). Hence, to drive 320 miles, a battery would weigh about 2,200 pounds, which is basically impossible for a mass market automobile.
The Energy Density is the energy per volume which for lithium ion is typically 250-750 kWh/L (kilowatts per hours per liter). The Specific Power is the amount of power deliverable per kilogram; approximately 250 to 340 W/kg. The Charge/Discharge Efficiency for lithium ion batteries is 80-90%. For example, if 100 kWh of energy is inputted into the battery only about 80-90% is recoverable to drive the vehicle's electric motor. The Self-Discharge Rate represents the inevitable discharging of the battery power with the passage of time. The figures (per month) are 8% at 21° C.; 15% at 40° C.; and 31% at 60° C., respectively. Thus, if the battery is kept at over 100° F., about 15% per month of the battery charge is passively lost. Cycle Durability reflects the inherent limit on the number of times a battery can be charged and discharged. For lithium ion batteries, it is typically 400-1200 cycles. Battery cells have inherent nominal voltages. For a NMC battery, it is 3.6/3.7 volts. Thus, 30 NMC batteries connected in series provide a nominal 108 volt DC output.
To date, the conventional approach has been to provide an entire battery assembly, that stays with the same vehicle for as long as the battery assembly lasts. The prior art does, however, describe systems for exchanging/swapping the battery assembly. Indeed, Tesla is offering quick swapping assembly stations. Better Place also provided such battery exchange stations. But the Better Place and Tesla exchange stations require investment of millions of dollars to handle batteries that weigh hundreds of pounds. We are very far away from the day where all neighborhood gas stations will have the capacity/ability to exchange 500+ pounds batteries for BEVs.
Battery swapping is described in U.S. Pat. No. 5,760,569. A vehicle tray slides from an openable door at the rear of the vehicle and the battery is slid within. A BEV owner or driver could never handle a battery that weighs 500 or 600 pounds in this manner. Besides, the exposed electrodes have a voltage potential of approximately 100 volts DC, which should not be handled at the private level. In U.S. patent publication 2010/0230188 the battery is located on wheels and somehow installed through vehicle side door openings. Several battery modules may be loaded into large vehicles such as a truck. This reference suggests that the battery module should be of a standard size. But still, each battery module can power the vehicle, requiring that it weigh hundreds of pounds. In U.S. Pat. No. 5,542,488, the battery module is inserted laterally into the trunk area of the car. Another battery can be loaded by inserting it laterally through an opening at one of the doors of the vehicle, which interferes with the desire to keep the car aesthetics intact. In U.S. Pat. No. 5,951,229, a battery for an BEV to drive 75 to 100 miles intervals is described as having a dimension of five feet wide, five feet long and nine inches in height, making it impossible to loan/unload at home.
The difficulty of mounting the battery packs or modules of the prior art is exemplified by U.S. Pat. No. 6,014,597, which shows an underground lift for raising and loading heavy BEV batteries. In U.S. Pat. No. 8,561,743, the Nissan Leaf® battery arrangement is shown. It is a very complicated arrangement of various battery modules located at the bottom of the vehicle. The entire assembly (FIG. 5) can be lifted and attached at the bottom of the vehicle. It weighs about 600 pounds. U.S. publication 2003/0209375 discloses, in FIG. 3A, battery modules stacked under the passenger compartment and at the bottom of the luggage compartment. An underground lifting mechanism is needed to lift and install the batteries. In U.S. Pat. No. 3,708,028, massively-sized battery packs are laterally inserted into the truck. In U.S. Pat. No. 5,711,648, a massive battery swapping system with an underground lift is provided to load and unload very heavy batteries. A similar underground battery swapping system is disclosed in U.S. Pat. No. 5,998,963. Complex, heavy duty battery conveying systems are also disclosed in U.S. Pat. No. 5,187,423. This document describes, at col. 1, that its goal is “using standard batteries in all vehicles and providing a standard battery replacement service capable of instantly replacing discharged batteries with charged ones”.
In U.S. Pat. No. 5,301,765, a hoisting system is used to lift a massive battery and to lower it into the engine compartment. The battery has electrodes that are inserted into female sockets. A complex battery swapping system is also disclosed in U.S. Pat. No. 5,612,606. It uses an underground system to lift very large and heavy batteries. A similar system is also described in U.S. Pat. No. 7,993,155 and in U.S. Pat. No. 8,454,377. See also U.S. Pat. No. 8,164,300. All of these battery exchange systems are very expensive, requiring millions of dollars in infrastructure initial costs. The prior art is also exemplified by U.S. Pat. Nos. 6,094,028; 5,631,536; 4,102,373; and 7,602,143. The entire contents of all of the foregoing patents and patent publications are incorporated by reference herein to provide a disclosure and teachings of known systems involved with electrical vehicles.
In a study commissioned by the California Air Resources Board (CARB), the authors report (in an article entitled “Life Cycle Analysis Comparison of a Battery Electric Vehicle and a Conventional Gasoline Vehicle” dated June 2012), the results of comparisons between conventional ICs, Hybrid vehicles and BEVs. At page 21, the report asserts that BEVs, under current battery technology, are actually more expensive to operate over their fifteen year life cycle than CVs and Hybrids. From the chart at page 20 of the Report, it appears that the initial cost for a BEV is roughly three times that of a conventional vehicle and twice that of the Hybrid.
Despite the investments of literally billions of dollars to date across the entire world, it remains so that pure electrical vehicles (BEVs) have not been adopted en masse by the regular purchasers, i.e., by those who cannot afford paying much more than $20,000 for a vehicle and require a vehicle that delivers more than a 100 mile driving range and very short “re-fueling” times. Therefore, under the current conditions, the electric vehicle will remain a niche vehicle, which is only purchased by die-hard environmentalists or persons who can afford to buy at any price or by people who have multiple cars, among which one is the BEV vehicle.
The aim of the present invention is to provide BEVs that avoid that high initial battery costs and make that high initial cost for the BEV comparable to and actually considerably lower than the costs of purchasing CVs and Hybrid vehicles, and with rapid and widely available and easy battery swapping.